Jerusalem - Israeli Prime Minister Benjamin Netanyahu said in a televised address Monday he had new "proof" of an Iranian nuclear weapons plan that could be activated at any time, as the US considers whether to pull out of the atomic accord with Tehran.

But while Netanyahu accused Israel's main enemy Iran of lying about its nuclear ambitions, he did not provide evidence that it had actively worked to obtain an atomic weapon since the 2015 agreement between Tehran and six world powers.

Iran has always denied it sought a nuclear weapon, insisting its atomic programme was for civilian purposes.

Netanyahu made the comments in an elaborate presentation that included props, video and slides, broadcast live on television from Tel Aviv.

He said Israel had obtained tens of thousands of files "a few weeks ago in a great intelligence achievement," saying they had been moved to a secret compound in Tehran in 2017 that looked dilapidated from the outside.

As he spoke, binders that he said held copies of original documents were on shelves behind him, as were cases containing CDs.

"Tonight we're going to reveal new and conclusive proof of the secret nuclear weapons programme that Iran has been hiding for years from the international community in its secret atomic archive," Netanyahu said.

"We're going to show you Iran's secret nuclear files."

He then laid out what he said was a years-old secret nuclear weapons programme stored away and which he could be put into action at any time.

- 'Dominate the Middle East' -

US President Donald Trump has a May 12 deadline to decide on whether or not to walk away from the nuclear deal, which he has derided as "insane" partly because its restrictions on Iran's nuclear activities begin expiring in 2025.

Most world powers however say the nuclear deal is working as intended for now and is the best way to keep Iran from acquiring the bomb.

The Israeli premier has repeatedly called for the accord -- which Iran signed with Britain, France, China, Russia, the United States and Germany -- to either be altered or scrapped.

He says the 2015 Iran nuclear agreement does not prevent Tehran from eventually obtaining nuclear weapons and says the lifting of sanctions has increased Tehran's ability to finance proxy militants in the Middle East.

Netanyahu also wants to see curbs on Iran's missile programme.

His presentation came after he met visiting US Secretary of State Mike Pompeo on Sunday and spoke with Trump by phone on Saturday.

Pompeo reiterated during the visit that Trump will withdraw from the nuclear deal with Iran "if we can't fix it".

He also joined Netanyahu in lashing out at Iran.

"Iran's ambition to dominate the Middle East remains," Pompeo said.

Rob Malley, a former official in president Barack Obama's administration, said on Twitter that "for those who have followed the Iranian nuclear file, there is nothing new in (Netanyahu's) presentation".

"All it does is vindicate need for the nuclear deal. But the Israeli prime minister has an audience of one: Trump. And he's unfortunately unlikely to reach the same conclusion."